1. Field
This disclosure relates to a positive active material for a rechargeable lithium battery, a method of preparing the same, and a rechargeable lithium battery including the same.
2. Description of Related Art
Lithium rechargeable batteries have recently drawn attention as power sources for small portable electronic devices. Lithium rechargeable batteries use an organic electrolyte solution, and thereby have twice the discharge voltage of conventional batteries using an alkaline aqueous solution, and accordingly lithium rechargeable batteries have high energy density.
A rechargeable lithium battery is fabricated by injecting an electrolyte into a battery cell. A battery cell includes a positive electrode including a positive active material capable of intercalating/deintercalating lithium ions and a negative electrode including a negative active material capable of intercalating/deintercalating lithium ions.
For a positive active material, LiCoO2 is widely used. However, since cobalt (Co) is a rare metal, costs for producing LiCoO2 are high and additionally, stable supplies of Co are difficult to secure. Accordingly, a positive active material including Ni (nickel) or Mn (manganese) has been researched.
A positive active material including Ni may provide a high capacity and high voltage battery. However, the structure of a Ni positive active material is unstable and thus capacity is reduced. Also, due to a reaction with the electrolyte solution, a Ni positive active material has weak thermal stability.